Coronary artery bypass graft (CABG) surgery has become a well known and conventional procedure, often referred to as "heart bypass" surgery. Such surgery is performed to relieve a condition in which a partially or fully blocked artery is no longer effective to transport blood to the heart and involves removing a portion of a vein from another part of the body, frequently the saphenous vein, to use as a graft and installing this graft at points which bypass the obstruction to restore normal blood flow to the heart. Common though this procedure has become, it is nevertheless lengthy, traumatic and subject to patient risk. Among the risk factors involved is the use of cardiopulmonary bypass equipment, i.e., the so-called "heart-lung machine," to both pump blood and oxygenate the blood so that the patient's heart may be stopped during the surgery, with its function performed by the cardiopulmonary bypass equipment.
Prior to the present invention, it has been found possible to conduct CABG surgery without stopping the heart, i.e., on a beating heart. In such a beating heart procedure, the function of the heart is maintained and the cardiopulmonary bypass equipment is not needed to replace that function. However, since the heart is beating in such a procedure, the surgeon must cope with the movement of the heart, whether the surgery is a bypass procedure or any other type of coronary surgery. Thus, it would be highly advantageous to perform coronary surgery on a stopped heart, but without causing the patient to endure the lengthy, traumatic and risky procedure involved in supporting the patient on cardiopulmonary bypass equipment. The present invention addresses this problem.
The performance of coronary surgery on the beating heart is described by Benetti et al in "Coronary Revascularization With Arterial Conduits Via a Small Thoracotomy and Assisted by Thoracoscopy, Although Without Cardiopulmonary Bypass", Cor. Europatum, 4(1):22-24 (1995), which is incorporated herein by reference and by Westaby, "Coronary Surgery Without Cardiopulmonary Bypass" in the March, 1995 issue of the British Heart Journal which is incorporated by reference herein. Additional discussion of this subject matter can be found in Benetti et al, Chest, 100(2):312-16 (1991), Pfister et al, Ann. Thorac. Surg., 54:1085-92 (1992), and Fanning et al, Ann. Thorac. Surg., 55:486-89 (1993). These articles discuss the further details of grafting by anastomosis of a saphenous vein or mammary artery to diseased coronary arteries including the left anterior descending artery (LAD) or the right coronary artery (RCA), temporary occlusion of the coronary artery to provide a bloodless anastomotic field, use of a double suture placed above and below the point of anastomosis, and use of a running suture for the anastomosis. These articles also contrast the beating heart procedure to the more widely used CABG method performed on the non-beating heart with cardiopulmonary bypass.